scholarly journals POST-CURE’S EFFECT ON THE DEPTH OF CURE OF A SHORT FIBER-REINFORCED RESIN COMPOSITE

2018 ◽  
Vol 9 ◽  
pp. 158
Author(s):  
Ellyza Herda ◽  
Nadia Safira Ninda ◽  
Mia Damiyanti
Keyword(s):  
Vickers Microhardness ◽  
Light Emitting Diode ◽  
Resin Composite ◽  
Short Fiber ◽  
T Test ◽  
Fiber Reinforced ◽  
Light Emitting ◽  
Depth Of Cure ◽  
Microhardness Profile ◽  
Light Curing

Objective: This study aimed to identify post-cure’s effect on the depth of cure (DOC) of a short fiber-reinforced resin composite (SFRC).Methods: Six EverX PosteriorTM shade A3 specimens were cured with a light-emitting diode light curing unit with 800 mW/cm2 of light irradiation for 20 s. The specimens were divided into two groups. The first was measured immediately post-cure and the second was measured 24-h post-cure. They were measured with a Vickers microhardness profile test. An independent t-test was used to analyze the significance of the differences between the DOC value and different variables.Results: The DOC of the specimens measured immediately post-cure was 3.02±0.02 mm. The DOC of the specimens measured 24-h post-cure was 3.93±0.03 mm.Conclusion: The DOC of the specimens measured 24-h post-cure was significantly higher than the DOC of the specimens measured immediately post-cure. Post-cure polymerization (24-h post-cure) can increase the DOC values of an SFRC.

scholarly journals Mechanical properties, volumetric shrinkage and depth of cure of short fiber-reinforced resin composite

2016 ◽  
Vol 35 (3) ◽  
pp. 418-424 ◽  
Author(s):  
Akimasa TSUJIMOTO ◽  
Wayne W. BARKMEIER ◽  
Toshiki TAKAMIZAWA ◽  
Mark A. LATTA ◽  
Masashi MIYAZAKI
Keyword(s):  
Mechanical Properties ◽  
Resin Composite ◽  
Short Fiber ◽  
Volumetric Shrinkage ◽  
Fiber Reinforced ◽  
Depth Of Cure

scholarly journals The effect of halogen bulb and light-emitting diode light curing units on temperature increase and fibroblast viability

F1000Research ◽  
2020 ◽  
Vol 9 ◽  
pp. 1369
Author(s):  
Georgia Memari Trava ◽  
Juliane Almeida Santos ◽  
Lucas Paula Ramos ◽  
Pamela Beatriz Rosário Estevam dos Santos ◽  
Amjad Abu Hasna ◽  
...  
Keyword(s):  
Temperature Increase ◽  
Light Emitting Diode ◽  
Resin Composite ◽  
Control Group ◽  
Cytotoxic Effects ◽  
Light Emitting ◽  
Parametric Data ◽  
Light Curing ◽  
Halogen Bulb ◽  
Non Parametric

Background: This study aimed to compare the temperature increase produced by halogen bulb (HAL) and light-emitting diode (LED) light curing units (LCUs) by irradiating dentin discs (0.5 mm and 1 mm thickness), and to evaluate their cytotoxic effects on fibroblast culture in the presence of dentin discs due to the increasing demand on resin composite restorations and teeth bleaching for esthetic purposes. Methods: A total of 20 bovine incisors were used to obtain dentin discs and divided into four experimental groups (n=10): HAL0.5: irradiation with halogen-tungsten bulb Curing Light XL 3000 at an intensity of 470 mW/cm2 over a dentin disc of 0.5 mm; LED0.5: irradiation with LED Optilight Max (GNATUS- Ribeirão Preto, SP, Brazil) at an intensity of 1200 mW/cm2 over a dentin disc of 0.5 mm; HAL1: irradiation as in HAL0.5 but over a dentin disc of 1 mm; LED1: irradiation as in LED0.5 but over a dentin disc of 1 mm. The temperature increase was measured using a digital thermometer and the cytotoxicity was evaluated using an MTT assay with a mouse fibroblast cell line (L929). Parametric Data were analyzed by ANOVA and Tukey and non-parametric data were analyzed by Kruskal Wallis with Conover-Iman for non-parametric data (all with α=0.05). Results: A significant statistical difference was found between the groups HAL0.5 and HAL1 and both were different of LED0.5 and LED1 which presented higher temperature. All the experimental groups were different of the control group (without irradiation), and promoted reduction of cellular viability. Conclusions: HAL LCU promoted a lower temperature change in the dentin compared to LED, regardless of the dentin thickness (0.5-1 mm). Both HAL and LED LCUs decreased fibroblast viability; however, LED promoted more significant cytotoxic effects.

scholarly journals Characterization of Experimental Short-Fiber-Reinforced Dual-Cure Core Build-Up Resin Composites

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2281
Author(s):  
Eija Säilynoja ◽  
Sufyan Garoushi ◽  
Pekka K. Vallittu ◽  
Lippo Lassila
Keyword(s):  
Fracture Toughness ◽  
Resin Composite ◽  
Rotating Disk ◽  
Monomer Conversion ◽  
Short Fiber ◽  
Flexural Properties ◽  
Resin Composites ◽  
Fiber Reinforced ◽  
Three Point Bending ◽  
Light Curing

As a core build-up material, dual-cured (DC) resin-based composites are becoming popular. The aim of this research was to investigate specific physical and handling properties of new experimental short-fiber-reinforced DC resin composites (SFRCs) in comparison to different commercial, conventional DC materials (e.g., Gradia Core, Rebilda DC, LuxaCore Z, and Visalys® CemCore). Degree of monomer conversion (DC%) was determined by FTIR-spectrometry using either self- or light-curing mode. The flexural strength, modulus, and fracture toughness were calculated through a three-point bending setup. Viscosity was analyzed at room (22 °C) and mouth (35 °C) temperatures with a rotating disk rheometer. The surface microstructure of each resin composite was examined with scanning electron microscopy (SEM). Data were statistically analyzed with analysis of variance ANOVA (p = 0.05). The curing mode showed significant (p < 0.05) effect on the DC% and flexural properties of tested DC resin composites and differences were material dependent. SFRC exhibited the highest fracture toughness (2.3 MPa m1/2) values and LuxaCore showed the lowest values (1 MPa m1/2) among the tested materials (p < 0.05). After light curing, Gradia Core and SFRCs showed the highest flexural properties (p < 0.05), while the other resin composites had comparable values. The novel DC short-fiber-reinforced core build-up resin composite demonstrated super fracture toughness compared to the tested DC conventional resin composites.

Effect of Thickness on Light Transmission and Vickers Hardness of Five Bulk-fill Resin-based Composites Using Polywave and Single-peak Light-emitting Diode Curing Lights

2019 ◽  
Vol 44 (1) ◽  
pp. 96-107 ◽  
Author(s):  
GA Maghaireh ◽  
RB Price ◽  
N Abdo ◽  
NA Taha ◽  
H Alzraikat
Keyword(s):  
Vickers Microhardness ◽  
Light Transmission ◽  
Light Emitting Diode ◽  
Surface Hardness ◽  
Single Peak ◽  
Distilled Water ◽  
Light Emitting ◽  
Radiant Exposure ◽  
Light Curing ◽  
Post Hoc

SUMMARY Objectives: This study compared light transmission through different thicknesses of bulk-fill resin-based composites (RBCs) using a polywave and a single-peak light-emitting diode light-curing unit (LCU). The effect on the surface hardness was also evaluated. Methods: Five bulk-fill RBCs were tested. Specimens (n=5) of 1-, 2-, 4-, or 6-mm thickness were photopolymerized for 10 seconds from the top using a polywave (Bluephase Style) or single–peak (Elipar S10) LCU, while a spectrophotometer monitored in real time the transmitted irradiance and radiant exposure reaching the bottom of the specimen. After 24 hours of storage in distilled water at 37°C, the Vickers microhardness (VH) was measured at top and bottom. Results were analyzed using multiple-way analysis of variance, Tukey post hoc tests, and multivariate analysis (α=0.05). Results: The choice of LCU had no significant effect on the total amount of light transmitted through the five bulk-fill RBCs at each thickness. There was a significant decrease in the amount of light transmitted as the thickness increased for all RBCs tested with both LCUs (p&lt;0.001). Effect of LCU on VH was minimal (ηp2=0.010). The 1-, 2-, and 4-mm-thick specimens of SDR, X-tra Fill, and Filtek Bulk Restorative achieved a VHbottom/top ratio of approximately 80% when either LCU was used. Conclusions: The total amount of light transmitted through the five bulk-fill RBCs was similar at the different thicknesses using either LCU. The polywave LCU used in this study did not enhance the polymerization of the tested bulk-fill RBCs when compared with the single-peak LCU.

Battery Charge Affects the Stability of Light Intensity from Light-emitting Diode Light-curing Units

2017 ◽  
Vol 42 (5) ◽  
pp. 497-504 ◽  
Author(s):  
A Tongtaksin ◽  
C Leevailoj
Keyword(s):  
Light Intensity ◽  
Light Emitting Diode ◽  
Resin Composite ◽  
Bottom Surface ◽  
Light Emitting ◽  
Led Light ◽  
Battery Charge ◽  
Light Intensities ◽  
Light Curing ◽  
The Stability

SUMMARY This study investigated the influence of battery charge levels on the stability of light-emitting diode (LED) curing-light intensity by measuring the intensity from fully charged through fully discharged batteries. The microhardness of resin composites polymerized by the light-curing units at various battery charge levels was measured. The light intensities of seven fully charged battery LED light-curing units—1) LY-A180, 2) Bluephase, 3) Woodpecker, 4) Demi Plus, 5) Saab II, 6) Elipar S10, and 7) MiniLED—were measured with a radiometer (Kerr) after every 10 uses (20 seconds per use) until the battery was discharged. Ten 2-mm-thick cylindrical specimens of A3 shade nanofilled resin composite (PREMISE, Kerr) were prepared per LED light-curing unit group. Each specimen was irradiated by the fully charged light-curing unit for 20 seconds. The LED light-curing units were then used until the battery charge fell to 50%. Specimens were prepared again as described above. This was repeated again when the light-curing units' battery charge fell to 25% and when the light intensity had decreased to 400 mW/cm2. The top/bottom surface Knoop hardness ratios of the specimens were determined. The microhardness data were analyzed by one-way analysis of variance with Tukey test at a significance level of 0.05. The Pearson correlation coefficient was used to determine significant correlations between surface hardness and light intensity. We found that the light intensities of the Bluephase, Demi Plus, and Elipar S10 units were stable. The intensity of the MiniLED unit decreased slightly; however, it remained above 400 mW/cm2. In contrast, the intensities of the LY-A180, Woodpecker, and Saab II units decreased below 400 mW/cm2. There was also a significant decrease in the surface microhardnesses of the resin composite specimens treated with MiniLED, LY-A180, Woodpecker, and Saab II. In conclusion, the light intensity of several LED light-curing units decreased as the battery was discharged, with a coincident reduction in the units' ability to polymerize resin composite. Therefore, the intensity of an LED light-curing unit should be evaluated during the life of its battery charge to ensure that sufficient light intensity is being generated.

Effect of Mold Type and Diameter on the Depth of Cure of Three Resin-Based Composites

2018 ◽  
Vol 43 (5) ◽  
pp. 520-529 ◽  
Author(s):  
MM AlShaafi ◽  
A AlQussier ◽  
MQ AlQahtani ◽  
RB Price
Keyword(s):  
Light Emitting Diode ◽  
Resin Composite ◽  
Oral Care ◽  
Test Method ◽  
Mold Material ◽  
Light Emitting ◽  
Depth Of Cure ◽  
Composites Materials ◽  
Multiple Comparison Test ◽  
Power Setting

SUMMARY Objective: To evaluate the effects of different mold materials, their diameters, and light-curing units on the mechanical properties of three resin-based composites (RBC). Methods and Materials: A conventional nano-filled resin composite (Filtek Supreme Ultra, 3M Oral Care, St Paul, MN, USA) and two bulk-fill composites materials, Tetric Evoceram Bulk fill (Ivoclar Vivadent, Schaan, Liechtenstein) and Aura Bulk Fill (SDI, Bayswater, VIC, Australia), were tested. A total of 240 specimens were fabricated using metal or white semitransparent Delrin molds that were 4 or 10 mm in diameter. The RBCs were light cured for 40 seconds on the high-power setting of either a monowave (DeepCure-S, 3M Oral Care) or polywave (Bluephase G2, Ivoclar Vivadent) light-emitting diode (LED) curing unit. The depth of cure was determined using a scraping test, according to the 2009 ISO 4049 test method. Data were analyzed using multivariate analysis of variance followed by Tukey multiple comparison test (p&lt;0.05). Results: In general, when used for 40 seconds, both LED curing lights achieved the same depth of cure (p=0.157). However, the mold material and its diameter had a significant effect on the depth of cure of all three RBCs (p&lt;0.0001). Conclusion: Curing with either the polywave or monowave LED curing light resulted in the same depth of cure in the composites. The greatest depth of cure was always achieved using the 10-mm-diameter Delrin mold. Of the three RBCs tested, both Tetric Bulk Fill and Aura achieved a 4-mm depth of cure when tested in the 10-mm-diameter metal mold. Tetric Bulk Fill was the most transparent and had the greatest depth of cure, and the conventional composite had the least depth of cure. Very little violet (&lt;420 nm) light penetrated through 6 mm of any of the RBCs.

scholarly journals The effects of halogen and light-emitting diode light curing on the depth of cure and surface microhardness of composite resins

2011 ◽  
Vol 14 (2) ◽  
pp. 136 ◽  
Author(s):  
BatuCan Yaman ◽  
Can Dörter ◽  
Dina Erdilek ◽  
BegümGüray Efes ◽  
Yavuz Gömeç ◽  
...  
Keyword(s):  
Light Emitting Diode ◽  
Composite Resins ◽  
Surface Microhardness ◽  
Light Emitting ◽  
Depth Of Cure ◽  
Light Curing

Composite Resin Microhardness: The Influence of Light Curing Method, Composite Shade, and Depth of Cure

2008 ◽  
Vol 9 (4) ◽  
pp. 43-50 ◽  
Author(s):  
Cesar Henrique Zanchi ◽  
Flávio Fernando Demarco ◽  
Camila Silveira de Araújo ◽  
Marcelo Thomé Schein ◽  
Sinval Adalberto Rodrigues
Keyword(s):  
Composite Resin ◽  
Light Emitting Diode ◽  
Curing Time ◽  
Light Emitting ◽  
Depth Of Cure ◽  
Quartz Tungsten Halogen ◽  
Light Curing ◽  
Curing Method ◽  
Hardness Values ◽  
Knoop Indenter

Abstract Aim The aim of this study was to investigate the influence of light curing method, composite shade, and depth of cure on composite microhardness. Methods and Materials Forty-eight specimens with 4 mm of depth were prepared with a hybrid composite (Filtek Z-100, 3M ESPE); 24 with shade A1 and the remaining with shade C2. For each shade, two light curing units (LCUs) were used: a quartz-tungsten-halogen (QTH) LCU (Optilight Plus - Gnatus) and a light emitting diode (LED) LCU (LEC 470 II - MM Optics). The LED LCU was tested using two exposure times (LED 40 seconds and LED 60 seconds). After 24-hour storage, three indentations were made at mm depth intervals using a Knoop indenter. Data were submitted to three-way analysis of variance (ANOVA) and Tukey's test (p<0.05). Results The three factors tested (light curing method, shade, and depth) had a significant influence on the composite microhardness (p<0.05). All groups presented similar hardness values in the first mm, except for composite shade C2 cured with LED for 40 seconds. The hardness decreased with depth, especially for shade C2 for 40 seconds. Increasing light-curing time with LED produced hardness values similar to the QTH. Conclusions The light curing method including variations of time, the depth of cure, and the composite shade influence the composite microhardness. Clinical Significance Clinicians should avoid thicker increments when working with composite restorations. Extended light-curing time might be indicated depending on the composite shade and on the light-curing device. Citation de Araújo CS, Schein MT, Zanchi CH, Rodrigues SA Jr, Demarco FF. Composite Resin Microhardness: The Influence of Light Curing Method, Composite Shade, and Depth of Cure. J Contemp Dent Pract 2008 May; (9)4:043-050.

scholarly journals The Effect of Irradiation Distance on Microhardness of Resin Composites Cured with Different Light Curing Units

2010 ◽  
Vol 04 (04) ◽  
pp. 440-446 ◽  
Author(s):  
Isil Cekic-Nagas ◽  
Ferhan Egilmez ◽  
Gulfem Ergun
Keyword(s):  
Light Emitting Diode ◽  
Resin Composite ◽  
Composite Layer ◽  
Hardness Test ◽  
Resin Composites ◽  
Plasma Arc ◽  
Light Emitting ◽  
Quartz Tungsten Halogen ◽  
Halogen Light ◽  
Light Curing

Objectives: The aim of this study was to compare the microhardness of five different resin composites at different irradiation distances (2 mm and 9 mm) by using three light curing units (quartz tungsten halogen, light emitting diodes and plasma arc).Methods: A total of 210 disc-shaped samples (2 mm height and 6 mm diameter) were prepared from different resin composites (Simile, Aelite Aesthetic Enamel, Clearfil AP-X, Grandio caps and Filtek Z250). Photoactivation was performed by using quartz tungsten halogen, light emitting diode and plasma arc curing units at two irradiation distances (2 mm and 9 mm). Then the samples (n=7/ per group) were stored dry in dark at 37°C for 24 h. The Vickers hardness test was performed on the resin composite layer with a microhardness tester (Shimadzu HMV). Data were statistically analyzed using nonparametric Kruskal Wallis and Mann-Whitney U tests.Results: Statistical analysis revealed that the resin composite groups, the type of the light curing units and the irradiation distances have significant effects on the microhardness values (P<.05).Conclusions: Light curing unit and irradiation distance are important factors to be considered for obtaining adequate microhardness of different resin composite groups. (Eur J Dent 2010;4:440-446)

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